The present invention relates to a switchgear including an air-insulated earthed disconnecting switch which performs earthing and disconnecting with air insulation.
Power receiving facilities are provided with switchgears which include a vacuum circuit breaker for cutting off load current or fault current, a disconnecting switch and an earthed switch for ensuring operator's safety during load maintenance checks, a detector for detecting system voltage or current, a protective relay, and the like.
As an example of such switchgears, JP-A-6-12948, for example, discloses a cubicle-type gas-insulated switchgear which includes a three-position earthed disconnecting switch with a rotor as a contactor and a vacuum valve in a metal container. The metal container is filled with SF6 gas as insulating gas.